Automatic pulse control unit for the drive of cutting machines for paper, cardboard or the like

ABSTRACT

An automatic pulse control means for use on machines employed for cutting paper, cardboard or the like, more especially for controlling the advance of the feed chuck of such machines, wherein the coupling disc of the magnetic coupling is constructed as a pulse generator, comprising teeth along the whole of its circumference which influence the field of a magnetic head in such a manner, that when one of said teeth comes within the range of said magnetic head the field of the latter is varied and generates a resulting pulse which operates an arbitrarily preset subtracting counter mechanism with the effect whereby when the zero position of the latter is reached, it transmits said pulse for the control of the magnetic coupling. The system may operate either as a cut-sequencing unit for executing cuts of uniform width when provided with a single counter, or for executing a cutting program featuring cuts of different width by providing a plurality of counters, on which different number of pulses and thereby different cutting widths can be preset by means of the preselector switch associated with the counter mechanism in both cases.

United States Patent [54] AUTOMATIC PULSE CONTROL UNIT FOR THE DRIVE OFCUTTING MACHINES FOR PAPER,

CARDBOARD OR THE LIKE 3 Claims, 2 Drawing Figs.

[52] US. Cl 192/127, 83/277, 83/522, 192/33, 192/142, 235/151.l1 [51]Int. Cl ..Fl6d 43/26, B23q 17/18 [50] FieldofSearch 310/111,

[56] References Cited UNITED STATES PATENTS 3,172,026 3/1965 Schuman235/151.11x 3,209,221 9/1965 Pugsley et a1. .235/15111 ux PrimaryExuminer-Malcolm A. Morrison Assistant Examiner- R. Stephen Dildine, JrvAllomey Holman & Stern ABSTRACT: An automatic pulse control means foruse on machines employed for cutting paper, cardboard or the like, moreespecially for controlling the advance of the feed chuck of suchmachines, wherein the coupling disc of the magnetic coupling isconstructed as a pulse generator, comprising teeth along the whole ofits circumference which influence the field of a magnetic head in such amanner, that when one of said teeth comes within the range of saidmagnetic head the field of the latter is varied and generates aresulting pulse which operates an arbitrarily preset subtracting countermechanism with the effect whereby when the zero position of the latteris reached, it transmits said pulse for the control of the magneticcoupling. The system may operate either as a cut-sequencing unit forexecuting cuts of uniform width when provided with a single counter, orfor executing a cutting program featuring cuts of different width byproviding a plurality of counters, on

which different number of pulses and thereby different cutting widthscan be preset by means of the preselector switch associated with thecounter mechanism in both cases.

AUTOMATIC PULSE CONTROL UNIT FOR THE DRIVE OF CUTTING MACHINES FORPAPER, CARDBOARD OR THE LIKE Thepresent invention relates to anautomatic pulse control unit, in particular for controlling the drive ofa machine employed for cutting paper, cardboard or the like.

It is already known to control the drives of machine tools and similarmachines by means of magnetic tapes read by magnetic heads. It isfurther known to execute this type of control by means of program discsscanned by mechanical, electronic or optical means, where the pulsesgenerated during the scanning of the program disc are fed to a counter,which then acts on the drive of these machines in accordance with thedesired operating sequence.

A digital control system of this kind has already been proposed for thedrive of the feed chuck of a paper-cutting machine, consisting of acontrol plate coupled with a driving spindle of the feed chuck, saidplate being optically scanned and transmitting the pulses through acounter to the drive motor.

All the known pulse-controlled drive units require the provision ofadditional elements to the machine to be controlled, namely the controldevices to be scanned, such as tapes, program discs or the like.

It is an object of the present invention to provide a pulse controlunit, which is so constructed and arranged that a predetermined programsequence can be carried out without additional machine elements such asprogram discs, or similar data carriers.

The present invention consists in an automatic pulse control means forcutting machines for papers, cardboard, or the like, wherein a couplingdisc of a magnetic coupling is constructed to serve bothas a drivingelement and as a control element for controlling the advance of a feedchuck for the automatic execution of a cutting program.

According to the invention, the coupling disc may be provided with teethalong its periphery, which influence the field of a magnetic head insuch a manner, that when a tooth comes into the range of the magnetichead, the field of the latter is varied, and the pulse thus producedactuates an arbitrarily preset counter with the effect whereby when thezero position of said counter is reached, it transmits this pulse-forthe control of the magnetic coupling.

The type of construction with a single machine element, namely acoupling disc, can control firstly the drive of a feed chuck spindle andsecondly can provide transmission or generation of pulses for theautomatic program control of said feed chuck.

In the accompanying drawings FIG. 1 shows a part of a paper-cuttingmachine with a control unit according to the present invention inschematical presentation; and

FIG. 2 shows the general arrangement of the device on a paper cuttingmachine, in side elevation.

In carrying the invention into effect by way of example a drawings showin FIGS. 1 and 2, the paper-cutting machine 1 constituted by the machineframe 2, the work table 3, the feed chuck 4, the drive motor 5, themagnetic coupling 6 and the control unit 7. In the position here shown,the coupling disc, which simultaneously constitutes the control-plate 8,is in cooperative contact with the driving spindle 9 of feed chuck 4.The control-plate 8 is actuated by the motor and the driving pulley 10,Le. rotated. During this rotation the teeth 11 of the control-orcoupling disc 8 enter into the range of the magnetic head 12 andgenerate pulses which are transmitted to the counting mechanism 13. Thesubtracting counter 13 comprises a preselector switch 14, by means ofwhich the desired number of pulses can be preset in the known manner.Each 2 tooth 11 of control disc 8 produces a pulse, so that when thenumber of the generated pulses equals the number preset by means of thepreselector switch, the subtracting counter returns to zero owing to theinverse counting sequence. On reaching the zero position, the counter 13transmits a driving pulse to the braking magnet 15 of magnetic coupling6,

whereby the coupling-or control disc 8 is attracted by the brakingmagnet, thus stopping the drive of spindle 9 of feed chuck .4. Duringthe revolution of the control disc 8 the feed chuck has executed apredetermined advancing movement, which corresponds to the preset numberof pulses of the preselector switch 14. During this movement, thematerial to be cut 16 was advanced by an equal measure, so that the cutcan now be carried out. After completion of the cut, a known automaticmeans again releases the coupling disc from the braking magnet 15, sothat it comes into cooperative contact with the driving spindle andeffects in the aforedescribed manner both the advance of the chuck andthe program control, i.e. the transmission of the pulses via themagnetic head 12 to the counter 13. This working cycleis repeated untilthe entire stock of paper 16 has been sectioned in accordance with thecutting width set by means of the number of pulses on the preselectorswitch.

When a counting mechanism of the kind here shown is used, cuts of equalwidth are executed over the entire length of the material, i.e. thecontrol serves as a cut-sequencing device. If, on the other hand, cutsof different widths have to be carried out, then a plurality of countersmust be provided in accordance with the number of different cuts, whichcounters then have to be set to diiferent number of pulses and thus tothe desired widths of cut by means of the preselector switch.

The device described above thus makes it possible to execute amultiplicity of cutting programs by providing the requisite counters.These cutting programs are moreover achieved without alteration in theconstruction and arrangement of the control disc and without alteringits double func' tion of drive and control element.

I claim:

1. Automatic pulse control means for cutting machines for paper,cardboard, or the like, comprising magnetic clutch means including arotatably coupling disk, said coupling disk having thereonpulse-producing means for producing signal pulses representative of thedegree of rotation of said disk; subtracting counter'means operativelyassociated with said pulse-producing means for counting the number ofpulses produced and subtracting the number of pulses from a presetvalue, and for producing a driving pulse when said subtracting pulsereaches zero; and breaking magnet means operatively connected to saidcounter means and adapted to break said coupling disk upon receipt of adriving pulse from said counter means.

2. Automatic pulse control means according to claim 1, wherein saidpulse-producing means comprises a plurality of teeth spaced about theperiphery of said coupling disk, said pulse control means furthercomprising a stationary magnetic head positioned adjacent to and spacedslightly from the periphery of said coupling disk, whereby rotation ofsaid coupling disk will cause said magnetic head to produce a singlepulse each time one of said teeth comes into proximity with saidmagnetic head, said magnetic head being operatively connected to saidsubtracting counter means to transmit said pulses to said counter means.

3. Automatic pulse control means as defined in claim 2, furthercomprising preselector switch means for presetting a desired value intosaid subtracting counter means, whereby the number of said signal pulsesrequired to return said subtracting counter to zero and hence toactivate said breaking magnet means may be preselected.

1. Automatic pulse control means for cutting machines for paper,cardboard, or the like, comprising magnetic clutch means including arotatably coupling disk, said coupling disk having thereonpulse-producing means for producing signal pulses representative of thedegree of rotation of said disk; subtracting counter means operativelyassociated with said pulseproducing means for counting the number ofpulses produced and subtracting the number of pulses from a presetvalue, and for producing a driving pulse when said subtracting pulsereaches zero; and breaking magnet means operatively connected to saidcounter means and adapted to break said coupling disk upon receipt of adriving pulse from said counter means.
 2. Automatic pulse control meansaccording to claim 1, wherein said pulse-producing means comprises aplurality of teeth spaced about the periphery of said coupling disk,said pulse control means further comprising a stationary magnetic headpositioned adjacent to and spaced slightly from the periphery of saidcoupling disk, whereby rotation of said coupling disk will cause saidmagnetic head to produce a single pulse each time one of said teethcomes into proximity with said magnetic head, said magnetic head beingoperatively connected to said subtracting counter means to transmit saidpulses to said counter means.
 3. Automatic pulse control means asdefined in claim 2, further comprising preselector switch means forpresetting a desired value into said subtracting counter means, wherebythe number of said signal pulses required to return said subtractingcounter to zero and hence to activate said breaking magnet means may bepreselected.